Method of mounting mems integrated circuits directly from wafer film frame

ABSTRACT

A method mounting a MEMS integrated circuit on a substrate. The method includes the steps of: (a) providing a film frame tape supported by a wafer film frame, the film frame tape having the plurality of MEMS integrated circuits releasably attached via respective frontsides to the film frame tape; (b) treating a backside surface oxide layer of each MEMS integrated circuit with liquid ammonia; (c) positioning a substrate at the backside of one of said MEMS integrated circuits; (d) positioning a bonding tool on a zone of the film frame tape aligned with the MEMS integrated circuit; and (e) applying a bonding force from the bonding tool so as to bond the backside of the MEMS integrated circuit to the substrate.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.12/711,256 filed Feb. 24, 2010, which is a continuation of U.S.application Ser. No. 11/766,052 filed Jun. 20, 2007, now issued as U.S.Pat. No. 7,678,667 all of which are herein incorporated by reference.

FIELD OF THE INVENTION

The present invention relates to the fabrication and bonding of MEMSintegrated circuits. It has been developed primarily to facilitateconstruction of printheads from a plurality of such printhead integratedcircuits.

CROSS REFERENCE TO RELATED APPLICATIONS

The following patents or patent applications filed by the applicant orassignee of the present invention are hereby incorporated bycross-reference.

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BACKGROUND OF THE INVENTION

The present Applicant has described previously how a pagewidth inkjetprinthead may be constructed from a plurality of abutting printheadintegrated circuits (also known as printhead ICs, printhead chips andprinthead dies). As described extensively in, for example, Applicant'sU.S. application Ser. No. 11/014,732 filed on Dec. 12, 2004 (thecontents of which is herein incorporated by reference), a pagewidthprinthead usually comprises a plurality of abutting printhead ICsattached to a liquid crystal polymer (LCP) ink manifold via an adhesiveintermediary layer, which is sandwiched between the LCP ink manifold andthe printhead ICs. The adhesive intermediary layer is typically alaser-drilled epoxy-coated polymer film.

The construction of such printheads presents a number of designchallenges. Firstly, the printhead ICs must be mounted with highprecision on the polymer film so that laser-drilled holes in the filmare aligned with backside ink supply channels in the printhead ICs.Secondly, the MEMS fabrication process for the printhead ICs shouldpreferably present the ICs in such a way that facilitates bonding ontothe intermediary layer.

Hitherto, the Applicant has described how backside MEMS processing of aprinthead wafer may be performed to provide individual printhead ICs(see, for example, U.S. Pat. No. 6,846,692, the contents of which isincorporated herein by reference). During backside MEMS processing, thebackside of the wafer is ground to a desired wafer thickness (typically100 to 300 microns) and ink supply channels are etched from a backsideof the wafer so as to form a fluidic connection between the backside,which receives ink, and nozzle assemblies on a frontside of the wafer.In addition, backside MEMS processing defines dicing streets in thewafer so that the wafer can be separated into the individual printheadICs. Finally, any photoresist in the wafer is ashed off using anoxidative plasma. The exact ordering of backside MEMS processing stepsmay be varied, although backside MEMS processing is typically performedafter completion of all frontside MEMS fabrication steps, in which thenozzle assemblies are constructed on the frontside of the wafer.

In the process described in U.S. Pat. No. 6,846,692, the individualprinthead ICs end up mounted, via their backsides, to a handling means.The handling means may be a glass handle wafer, with the printhead ICsattached thereto via a releasable adhesive tape e.g. UV-release tape orthermal-release tape. Alternatively, the handling means may be a waferfilm frame, with the printhead ICs being attached to a dicing tapesupported by the wafer film frame. Wafer film frame arrangements will bewell known to the person skilled in the art.

The printhead ICs may be picked off individually from the handling means(for, example, using a robot) and either packaged or bonded directly toan intermediary substrate to construct a printhead. U.S. Pat. No.6,946,692 describes how a vacuum pick-up may be used in combination witha reciprocating x-y wafer stage and a UV lamp/mask to remove individualprinthead ICs from a glass handle wafer.

However, a problem with the process described in U.S. Pat. No. 6,846,692is that the individual printhead ICs must be removed from the handlingmeans and then aligned and bonded with high accuracy to the intermediarysubstrate. Whilst robot handling of the ICs helps to improve alignmentaccuracies, there are inevitable alignment losses in such a process.

It would be desirable to provide a process for removing MEMS devices,such as printhead ICs, from a handling means, which facilitatesalignment of the devices when bonded to a further substrate, such theintermediary substrate described above.

It would be further desirable to provide a process for printheadconstruction, which facilitates the use of alternative non-polymericintermediary substrates. Polymeric adhesive layers are inexpensive andconvenient to handle, but suffer from comparatively high thermalexpansion relative to the silicon printhead ICs and the LCP ink supplymanifold. A comparatively high coefficient of thermal expansion for theintermediary substrate exacerbates alignment problems duringconstruction and may even lead to loss of alignment over the duration ofthe printhead lifetime.

SUMMARY OF THE INVENTION

In a first aspect the present invention provides a method of bonding anintegrated circuit to a substrate, said integrated circuit being one ofa plurality of integrated circuits each having a respective frontsidereleasably attached to a film frame tape supported by a wafer filmframe, said method comprising the steps of:

-   -   (a) positioning a substrate at a backside of said integrated        circuit;    -   (c) positioning a bonding tool on a zone of said film frame        tape, said zone being aligned with said integrated circuit; and    -   (c) applying a bonding force from said bonding tool, through        said film frame tape and said integrated circuit, onto said        substrate,        thereby bonding said backside of said integrated circuit to said        substrate.

In a further aspect there is provided a method, further comprising thestep of:

-   -   removing said bonding tool from said tape.

Optionally, said film frame tape is a UV-release tape.

In a further aspect there is provided a method, further comprising thestep of:

-   -   exposing said zone of said film frame tape to UV radiation and        releasing said bonded integrated circuit from said tape.

Optionally, said integrated circuit is a MEMS integrated circuit.

Optionally, said integrated circuit is a printhead integrated circuit.

Optionally, steps (a) to (c) are repeated so as to construct a printheadon said substrate, said printhead comprising a plurality of abuttingprinthead integrated circuits.

Optionally, said substrate has a plurality of ink supply holes definedtherein, wherein one or more of said holes are aligned with ink supplychannels defined in the backside of said printhead integrated circuit.

Optionally, said substrate is an intermediary substrate for attachmentof said printhead integrated circuit to an ink supply manifold.

Optionally, said intermediary substrate is an adhesive polymer film.

Optionally, said intermediary substrate is a rigid member having acoefficient of thermal expansion within about 20% of the coefficient ofthermal expansion of the printhead integrated circuit and/or the inksupply manifold.

Optionally, said intermediary substrate is a glass member.

Optionally, a backside of each of the plurality of integrated circuitsis pre-treated for bonding to said intermediary substrate.

Optionally, said backside comprises an oxide layer.

Optionally, said oxide layer is pre-treated with liquid ammonia.

In a second aspect the present invention provides a method ofconstructing a printhead using a plurality of printhead integratedcircuits, each of said printhead integrated circuits having a respectivefrontside releasably attached to a film frame tape supported by a waferfilm frame, said method comprising the steps of:

-   -   (a) positioning a substrate at a backside of one of said        printhead integrated circuits;    -   (c) positioning a bonding tool on a zone of said film frame        tape, said zone being aligned with said printhead integrated        circuit;    -   (c) applying a bonding force from said bonding tool, through        said film frame tape and said printhead integrated circuit, onto        said substrate, thereby bonding said backside of said printhead        integrated circuit to said substrate;    -   (d) repeating steps (a) to (c) so as to construct a printhead on        said substrate, wherein said printhead comprises a predetermined        number of abutting printhead integrated circuits.

Optionally, said substrate comprises a plurality of ink supply holesdefined therein, each of said holes being aligned with an ink supplychannel defined in the backside of said printhead.

Optionally, said substrate is a glass member.

In a further aspect there is provided a method, further comprising thestep of:

-   -   bonding said substrate to an ink supply manifold such that said        substrate is sandwiched between said printhead and said ink        supply manifold.

Optionally, said printhead is a pagewidth inkjet printhead.

BRIEF DESCRIPTION OF THE DRAWINGS

Optional embodiments of the present invention will now be described byway of example only with reference to the accompanying drawings, inwhich:

FIG. 1 is a front perspective view of a printhead assembly;

FIG. 2 is an exploded front perspective view the printhead assemblyshown in FIG. 1;

FIG. 3 is an exploded rear perspective view the printhead assembly shownin FIG. 1;

FIG. 4 is a side-sectional view of the printhead assembly shown in FIG.1;

FIG. 5 shows a wafer assembly having a plurality of nozzles protected bya protective layer;

FIG. 6 shows the wafer assembly of FIG. 5 after attachment of anadhesive tape to the protective layer;

FIG. 7 shows the wafer assembly of FIG. 6 after attachment of a handlewafer to the adhesive tape;

FIG. 8 shows the wafer assembly of FIG. 7 flipped for backsideprocessing;

FIG. 9 shows the wafer assembly of FIG. 8 after backside processing,which includes defining dicing streets in the wafer;

FIG. 10 shows the wafer assembly of FIG. 9 after attachment of abackside handle wafer using an adhesive tape;

FIG. 11 shows the wafer assembly of FIG. 10 after releasing thefrontside handle wafer and tape;

FIG. 12 shows the wafer assembly of FIG. 11 flipped;

FIG. 13 shows the wafer assembly of FIG. 12 after ashing the protectivelayer;

FIG. 14 shows the wafer assembly of FIG. 13 with individual chips beingremoved;

FIG. 15 shows the wafer assembly of FIG. 13 attached mounted to a waferfilm frame;

FIG. 16 shows the assembly of FIG. 15 with the second handle wafer andtape partially removed;

FIG. 17 shows a printhead integrated circuit being bonded to anintermediary substrate;

FIG. 18 shows a bonded printhead integrated circuit being detached froma film frame tape; and

FIG. 19 shows the bonded printhead integrated circuit separated from thewafer film frame.

DESCRIPTION OF OPTIONAL EMBODIMENTS Printhead Assembly

A constructed printhead assembly 22 for a pagewidth printer (not shown)is shown in FIGS. 1 to 4. The printhead assembly 22 generally comprisesan elongate upper member 62 having a plurality of projecting U-shapedclips 63. These clips 63 are captured by lugs (not shown) formed in amain body (not shown) of the printer to secure the printhead assembly 22thereto.

The upper element 62 has a plurality of feed tubes 64 that receive inkfrom ink reservoirs (not shown) in the printer. The feed tubes 64 may beprovided with an outer coating to guard against ink leakage.

The upper member 62 is made from a liquid crystal polymer (LCP) whichoffers a number of advantages. It can be molded so that its coefficientof thermal expansion (CTE) is similar to that of silicon. It will beappreciated that any significant difference in the CTE's of theprinthead integrated circuit 74 (discussed below) and the underlyingmoldings can cause the entire structure to bow. LCP also has arelatively high stiffness with a modulus that is typically 5 times thatof ‘normal plastics’ such as polycarbonates, styrene, nylon, PET andpolypropylene.

As best shown in FIG. 2, upper member 62 has an open channelconfiguration for receiving a lower member 65, which is bonded thereto,via an adhesive film 66. The lower member 65 is also made from an LCPand has a plurality of ink channels 67 formed along its length. Each ofthe ink channels 67 receives ink from one of the feed tubes 64, anddistributes the ink along the length of the printhead assembly 22. Thechannels are 1 mm wide and separated by 0.75 mm thick walls.

In the embodiment shown, the lower member 65 has five channels 67extending along its length. Each channel 67 receives ink from only oneof the five feed tubes 64.

In the bottom of each channel 67 are a series of equi-spaced holes 69(best seen in FIG. 3) to give five rows of holes 69 in the bottomsurface of the lower member 65. The middle row of holes 69 extends alongthe centre-line of the lower member 65, directly above the printhead IC74.

Referring to FIG. 4, the printhead ICs 74 are mounted to the undersideof the lower member 65 by a polymer sealing film 71. This film may be athermoplastic film such as a PET or polysulphone film, or it may be inthe form of a thermoset film, such as those manufactured by ALtechnologies and Rogers Corporation. The polymer sealing film 71 is alaminate with adhesive layers on both sides of a central web, andlaminated onto the underside of the lower member 65. As shown in FIG. 3,a plurality of holes 72 are laser drilled through the adhesive film 71to coincide with the centrally disposed ink delivery points (the middlerow of holes 69 and the ends of the conduits 70) for fluid communicationbetween the printhead ICs 74 and the channels 67.

The printhead ICs 74 are arranged to extend horizontally across thewidth of the printhead assembly 22. To achieve this, individualprinthead ICs 74 are linked together in abutting arrangement to form aprinthead 56 across the surface of the adhesive layer 71, as shown inFIGS. 2 and 3.

As described in the Applicant's Applicant's earlier U.S. applicationSer. No. 11/014,732 filed on Dec. 12, 2004 (Attorney Docket No.RRC020US), the printhead ICs 74 may be attached to the polymer sealingfilm 71 by heating the ICs above the melting point of the adhesive layerand then pressing them into the sealing film 71. Alternatively, theadhesive layer under each IC may be melted with a laser before pressingthem into the film. Another option is to heat both the IC (not above theadhesive melting point) and the adhesive layer, before pressing the ICinto the film 71. As alluded to above, this method of printheadfabrication has inherent alignment problems.

Following attachment and alignment of each of the printhead ICs 74 tothe surface of the polymer sealing film 71, a flex PCB 79 (see FIG. 4)is attached along an edge of the ICs 74 so that control signals andpower can be supplied to the bond pads on the ICs and control andoperate inkjet nozzles. As shown more clearly in FIG. 1, the flex PCB 79folds around the printhead assembly 22.

The flex PCB 79 may also have a plurality of decoupling capacitors 81arranged along its length for controlling the power and data signalsreceived. As best shown in FIG. 2, the flex PCB 79 has a plurality ofelectrical contacts 180 formed along its length for receiving powerand/or data signals from control circuitry of the printer. A pluralityof holes 80 are also formed along the distal edge of the flex PCB 79which provide a means for attaching the flex PCB to complementaryconnectors in the printer.

As shown in FIG. 4, a media shield 82 protects the printhead ICs 74 fromdamage which may occur due to contact with the passing media. The mediashield 82 is attached to the upper member 62 upstream of the printheadICs 74 via an appropriate clip-lock arrangement or via an adhesive. Whenattached in this manner, the printhead ICs 74 sit below the surface ofthe media shield 82, out of the path of the passing media.

Backside MEMS Processing Described in U.S. Pat. No. 6,846,692

FIGS. 5 to 14 outline typical backside MEMS processing steps, asdescribed in U.S. Pat. No. 6,846,692 (the contents of which is hereinincorporated by reference), for fabrication of the printhead ICs 74. Inan initial step, illustrated at 210 in FIG. 5, a silicon wafer 212 isprovided having a frontside 216 on which is formed a plurality of MEMSnozzle assemblies 218 in a MEMS layer 214. The MEMS nozzle assemblies218 typically comprise a sacrificial material, which fills nozzlechambers.

A protective layer 220 is interposed between the nozzle assemblies 218.This protective layer 220 is typically a relatively thick layer (e.g. 1to 10 microns) of sacrificial material, such as photoresist, which isspun onto the frontside 216 after fabrication of the MEMS nozzleassemblies 218. The photoresist is UV cured and/or hardbaked to providea rigid and durable protective coating that is suitable for attachmentto a glass handle wafer.

A first holding means, in the form of an adhesive tape 222, is bonded tothe MEMS layer 14 as illustrated in FIG. 6. The tape 222 is bonded tothe layer 214 by means of a curable adhesive. The adhesive is curable inthe sense that it loses its adhesive properties or “tackiness” whenexposed to ultraviolet (UV) light or heat. The tape 222 described in thespecific embodiment herein is a UV-release tape, although it will beappreciated that thermal-release tapes are equally suitable for use asthe first holding means.

As shown in FIG. 7, a first handle wafer 224, in the form of a glass,quartz, alumina or other handle wafer, is secured to the tape 222.

A laminate 226, comprising the silicon wafer 212 with MEMS layer 214,the tape 222 and the glass wafer 224 is then turned over to expose anopposed backside 228 of the wafer.

The backside 228 of the silicon wafer 212 is then thinned bybackgrinding a surface 228.1, as illustrated in FIG. 8. Wafer thinningmay include plasma thinning to remove any surface cracks or indentationsresulting from backgrinding.

Then, as shown in FIG. 9, the silicon wafer 212 is deep silicon etchedthrough the wafer from the backside 228 to dice the wafer 212 and formindividual integrated circuits 74. In FIG. 9, each IC 74 has only oneMEMS nozzle assembly 218 associated therewith, although it will beappreciated that each IC typically contains an array (e.g. greater than2000) nozzle assemblies arranged in rows.

At the same time as etching dicing streets from the backside 228 of thewafer 212, ink supply channels may also be etched so as to provide afluidic connection to each nozzle assembly 218.

Following backside etching, and as shown in FIG. 10, a second holdingmeans in the form of a second adhesive tape 232 (e.g. UV-release tape orthermal-release tape) is bonded to the backside surface 228.1 of thewafer 212, and a second handle wafer 234 is bonded to the tape 232.

After attachment of the second handle wafer 234, the first tape 222 andthe glass wafer 224 are removed, as illustrated schematically by arrow236 in FIG. 11. The tape 222 may be removed by exposing it to UV lightwhich is projected on to the tape 222 through the glass layer 224 asillustrated by arrows 238. It will be appreciated that the glass wafer224 is transparent to the UV light. In contrast, the silicon wafer 212is opaque to the UV light so that the tape 232 on the other side of thewafer 212 is not affected by the UV light when the tape 222 is exposedto the UV light.

Referring to FIG. 12, once the tape 222 and glass wafer 224 have beenremoved, a new laminate 240, comprising the silicon wafer with MEMSlayer 214, the second tape 232 and the glass wafer 234 is turned over toexpose the protective layer 220.

Referring to FIG. 13, the protective layer 220 is then removed by ashingin an oxygen plasma. This releases the MEMS nozzle assemblies 218, andcompletes the separation of the ICs 74. At the same time as removing theprotective layer 220, any other exposed sacrificial material, whichremained from frontside MEMS fabrication, is also removed.

The laminate 240 is then placed on an xy wafer stage (not shown) whichis reciprocated, as illustrated by arrow 244 in FIG. 14. Each IC 74,when it is desired to remove it, is exposed to UV light as indicated byarrows 246 through a mask 250. This cures the adhesive of the tape 232locally beneath one particular IC 74 at a time, to enable that IC to beremoved from the tape 232 by means of a transporting means which mayinclude a vacuum pickup 248. The printhead ICs 74 can then be packagedand/or formed into a printhead by butting a plurality of ICs together.

Alternative Backside MEMS Processing and Printhead Construction

A shortcoming of the backside MEMS process described above is that theprinthead ICs 74 must be individually removed from the second handlewafer 234 and then assembled into the printhead 56 by attaching them toan intermediary substrate, such as the adhesive film 71. This processhas inherent alignment difficulties.

FIGS. 15 to 19 show an alternative sequence of backside MEMS processingsteps, which avoids picking ICs 74 individually from the second handlewafer 234, as shown in FIG. 14. Instead the ICs 74 are bonded directlyonto an intermediary substrate 302 from a wafer film frame 300, as willbe described in more detail below.

Starting from the assembly 240 shown in FIG. 13, the array of printheadICs 74 attached to the second handle wafer 234 is mounted to a waferfilm frame 300, as shown in FIG. 15. The frontside 216 of each printheadIC 74 is attached to a film frame tape 301 supported by the wafer filmframe 300. Whilst the size of the MEMS devices 218 is shown exaggeratedin FIG. 15, it will be appreciated that the printhead ICs 74 have asubstantially planar frontside 216 which bonds to the film frame tape301.

It is important that the first tape 222 and second tape 232 arecomplementary with the film frame tape 301 supported by the wafer filmframe 300. Accordingly, in this embodiment it is preferred that thefirst tape 222 and second tape 232 are thermal-release tapes (e.g. 150°C. thermal release tape and 170° C. thermal release tape), and the filmframe tape 301 is a UV-release tape. Thus, the array of printhead ICs 74can be mounted to the film frame tape 301 and then the second handlewafer 234 with second tape 232 removed from the array by heating.

Referring to FIG. 16, there is shown the second handle wafer 234(together with second tape 232) being removed from the backside 228 ofthe array of ICs 74. This may be achieved by simply heating thethermal-release tape 232. After this step, the printhead ICs 74 aremounted via their frontsides 216 to the film frame tape 301. Thebacksides 228 of the printhead ICs 74, which will be attached to the LCPmember 65, are exposed and ready for bonding.

After removal of the second handle wafer 234 and tape 232, the exposedbacksides 228 of the ICs may be treated for subsequent bonding. Forexample, the backsides 228 may be treated for bonding using theproprietary Zibond™ bonding process, developed by Ziptronix, Inc. Thisprocess typically requires an oxide surface to be treated with liquidammonia, which prepares the surface for bonding to a range ofsubstrates. The backsides 228 of the ICs 74 may be coated with a layerof oxide at an earlier stage of backside MEMS processing (for example,at the stage shown in FIG. 8—that is, prior to etching backside dicingstreets and ink supply channels). Ammonia treatment of this backsideoxide layer may then be performed with the ICs 74 mounted on the waferfilm frame 300. The present invention is particularly suited for theZibond™ bonding process, because there is minimal handling of the ICs 74between backside treatment and subsequent bonding.

Alternatively, the backsides 228 of the ICs 74 may be left untreated andbonded to an intermediary substrate, such as the adhesive film 71, usingmore conventional adhesive bonding methods.

The principal advantages of the present invention are realized by thesequence of steps represented by FIGS. 17 to 19. Instead of removing theICs 74 from the wafer film frame 300, the backsides 228 are bondeddirectly to an intermediary substrate 302, whilst still attached to thefilm frame tape 301. A bonding tool 303 may be employed to select andbond an individual IC 74 onto a predetermined position of theintermediary substrate 302, as shown in FIG. 17. The use of the bondingtool 303 in combination with the wafer film frame 300 ensureshigh-precision bonding of individual printhead ICs 74 to theintermediary substrate 302.

The intermediary substrate 302 may be the laser-drilled adhesive film 71described earlier. Alternatively, the intermediary substrate 302 may bea rigid, glass member, which takes the place of the adhesive film 71 inbonding the printhead ICs 74 to the LCP member 65. A glass member isadvantageous, because it has a similar coefficient of thermal expansionto the LCP member 65 and the printhead ICs 74. The skilled person willappreciate that the glass member may be pre-etched with ink supply holescorresponding to the laser-drilled holes 72 of the polymer film 71.

Hence, it will be appreciated that the present invention improvesalignment of the printhead ICs 74 with the intermediary substrate 302.Alignment is improved firstly by performing the bonding step with theprinthead ICs 74 still mounted on the wafer film frame 300. Secondly,the present invention facilitates the use of intermediary substrates 302other than the polymeric adhesive film 71 described earlier. In avoidingthe use of the polymeric adhesive film 71, alignment errors resultingfrom differential thermal expansion are further minimized.

Once the printhead IC 74 is bonded to the intermediary substrate 302,the bonding tool is removed and the bonded IC 74 detached from the filmframe tape 301. As shown in FIG. 18, this may achieved by selectivelyUV-curing a zone of the tape 301. A suitable mask 304 may be employedfor selective UV-curing.

Finally, as shown in FIG. 19, the intermediary substrate 302 with the IC74 bonded thereto is separated fully from the wafer film frame 300. Thebonding process illustrated in FIGS. 17 to 19 may be repeated along thelength of the intermediary substrate 302 so as to build up the printhead56 from a plurality of abutting printhead ICs 74.

Once the printhead 56 is fully constructed, an opposite face of theintermediary substrate 302 is attached to the LCP member 65, asdescribed above, to form the printhead assembly 22.

It will be appreciated by ordinary workers in this field that numerousvariations and/or modifications may be made to the present invention asshown in the specific embodiments without departing from the spirit orscope of the invention as broadly described. The present embodimentsare, therefore, to be considered in all respects to be illustrative andnot restrictive.

1. A method of mounting a MEMS integrated circuit on a substrate, saidmethod comprising the steps of: (a) providing a film frame tapesupported by a wafer film frame, said film frame tape having a pluralityof MEMS integrated circuits releasably attached via respectivefrontsides to said film frame tape, wherein a backside of each MEMSintegrated circuit has a surface oxide layer; (b) treating the surfaceoxide layer with liquid ammonia; (c) positioning a substrate at thebackside of one of said MEMS integrated circuits; (d) positioning abonding tool on a zone of said film frame tape, said zone being alignedwith said MEMS integrated circuit; and (e) applying a bonding force fromsaid bonding tool, through said film frame tape and said MEMS integratedcircuit, onto said substrate, thereby bonding said backside of said MEMSintegrated circuit to said substrate.
 2. The method of claim 1, whereinsaid MEMS integrated circuit is a printhead integrated circuit.
 3. Themethod of claim 2, further comprising: repeating steps (c) to (e) so asto construct a printhead on said substrate, wherein said printheadcomprises a predetermined number of abutting printhead integratedcircuits.
 4. The method of claim 3, wherein said substrate has aplurality of ink supply holes defined therein, each of said holes beingaligned with an ink supply channel defined in the backside of saidprinthead.
 5. The method of claim 4, wherein said substrate is comprisedof glass.
 6. The method of claim 4, further comprising the step of:bonding said substrate to an ink supply manifold such that saidsubstrate is sandwiched between said printhead and said ink supplymanifold.
 7. The method of claim 3, wherein said printhead is apagewidth inkjet printhead.